1. Field of the Invention
The present invention concerns a pneumatic screwdriver.
The invention is directed to a pneumatic screwdriver having a body with means for connection to a compressed air feed hose at one end and a tool at the other end, said body containing a pneumatic motor driving a tool through a kinematic coupling with an interposed torque limiter.
2. Description of the Prior Art
Screwdrivers of this kind are well known and in widespread use in many industries to assemble parts very fast with the assurance that screws and nuts are tightened to a constant torque.
One drawback of the torque limiters provided in such screwdrivers is that they are complex, bulky and generate friction with the result that the tightening torque is not constant. Moreover, they are difficult to adjust. Finally, it is difficult to mass produce torque limiters having a tightening torque of consistent accuracy.
Another drawback is that after the tool has stopped when the required torque is achieved the motor, which rotates at high speed, continues to rotate, which causes modification of the next torque value.
One aim of the present invention is to remedy these various drawbacks.